1. Field of the Invention
The invention relates in general to a positioning mechanism and a display device using the same, and more particularly to a positioning mechanism that achieves the function of positioning by engaging a buckling element to a positioning pin and a display device using the same.
2. Description of the Related Art
Recent years, consumers request for a higher standard of visual presentation of display devices. Compared with the conventional aspect ratio of 4:3, the wide-screen aspect ratio of 16:9 or 16:10 provides extended and better visualization. This makes the display device with wide-screen aspect ratio become more and more popular. In accordance with the requirement of users, the display devices with wide-screen aspect ratio are designed to be capable of switching between a horizontal displaying state and a vertical displaying state, and a pivotal positioning mechanism is required for rotating and positioning the display monitor.
Referring to FIG. 1, a side view of a pivotal positioning mechanism of a conventional display device is shown. The pivotal positioning mechanism 10 comprises a fixed frame 11, a rotary component 12, a first pad w1, a second pad w2 and a rotary shaft 13. The fixed frame 11 is used for connecting the supporting base (not illustrated in the diagram) of the display device. The rotary component 12 is used for connecting the display monitor 15 of the display device. The first pad w1 is connected to the fixed frame 11 and has a number of positioning protrusions 14a. The second pad w2 is connected to the rotary component 12. The second pad w2 further has a number of positioning cavities 14b corresponding to these positioning protrusions 14a of the first pad w1. The rotary component 12 is pivotally connected to the fixed frame 11 via the rotary shaft 13. The rotary component 12 is rotated around the rotary shaft 13 with respect to the fixed frame 11. The conventional positioning mechanism 10 positions the display device by enabling positioning cavities 14b to be engaged to the positioning protrusions 14a. 
However, due to the tight engagement of the first pad w1 and the second pad w2, when the first pad w1 and the second pad w2 are rotated relatively, the positioning protrusions 14a and the second pad w2 are apt to be worn out due to friction, and incapacitating the positioning protrusion 14a to be engaged to the positioning cavities 14b. Therefore, the display monitor 15 is mal-positioned by the pivotal positioning mechanism 10, and the display monitor 15 cannot be positioned accurately. To the worse, when the pivotal positioning mechanism 10 rotates, the display monitor 15 may tilt or end up with a skewed angle, and affects the appearance of the display device. After a long duration of service, the conventional pivotal positioning mechanism 10 is apt to inaccurate positioning, hence reducing the accuracy of positioning. Consequently, the practicality of the display device is reduced.